A few positions are especially rich -- e.g. running back and offensive line -- but others leave room for declared juniors to emerge as top prospects. The Senior Bowl squads will be coached by two current NFL staffs (Vikings and Redskins), adding an extra dimension to their evaluations.

Just like my Shrine Week coverage, I will be constantly tweeting (@JoshNorris) and producing frequent articles. For now, here is a position-by-position preview along with my top 15 prospects entering the week. Tomorrow, I will post evaluations on players that opted out of the Senior Bowl.

All heights, weights, and forty times are projected until weigh-ins take place early Monday.

Quarterbacks

Age can be a factor when selecting a quarterback early, but Oklahoma State’s Brandon Weeden (6-4/218/4.92) may be an exception to the rule. He will be 28 once the 2012 season kicks off after exploring Minor League Baseball, but stands tall in the pocket with patience and delivers an accurate ball into tight windows. The former pitcher has NFL velocity, and Weeden's release is quick when his feet are set. If a quarterback-needy team believes it can win right away with Weeden, it should not hesitate to draft him early.

Arizona’s Nick Foles (6-5/240/4.96) has gained steam lately, with some attributing his ups and downs to a poor offensive line. Whatever the excuse, Foles is an incredibly inconsistent passer. At times he flashes the ability to make every NFL throw, but too often Foles’ lack of mobility, dropping release, and erratic decision-making lead to trouble when his feet aren't set. Wisconsin’s Russell Wilson (5-11/210/4.59) and Boise State's Kellen Moore (6-0/195/4.98) will both measure in below six feet and need to break the mold of solid college quarterbacks that lack arm talent and height to succeed at the next level.

Running Backs

A versatile, deep group of ball carriers has made its way to Mobile hoping to change the perception that their position isn't worth early-round picks due to a historically short shelf life. Boise State's Doug Martin (5-9/210/4.48) has been labeled as a power back because of his thick stature, but along with rarely going down on first contact Martin has great balance and breaks plenty of tackles. He explodes through holes with nice posture and does not lack straight-line speed. Martin has the skills of a future three-down back with soft hands and experience in pass protection. The lone issue is that Martin lacks wiggle to make defenders miss in the open field.

Closely behind is Washington’s Chris Polk (5-11/222/4.48), whose best assets are patience and vision. A tackle breaker himself, Polk follows his downfield blocks closely by weaving in and out of lanes and uses deceptive long speed to bust into the open field. Polk is another potential three-down back that has soft hands and gives effort in pass protection.

Cincinnati's Isaiah Pead (5-10/200/4.42) is a versatile playmaker with sure hands that seems to break at least one long run each game. He made his living in college with shifty moves in short spaces and excellent vision, but Pead's explosion out of breaks is not as quick as it should be for a runner that uses it as a crutch. DeMarco Murray faced similar criticism, but his skills have translated to be an effective open-field runner. Pead will need to do the same. Mississippi State’s Vick Ballard (5-10/220/4.58) and Baylor’s Terrance Ganaway (5-11/240/4.62) are between-the-tackles runners that break long runs on occasion but go down on first contact too often and have little short-area quickness to suddenly change direction.

Wide Receivers/Tight Ends

With top-rated seniors Floyd and Wright out, the rest of this year's Senior Bowl receiver group has increased opportunity to catch scouts' attention. UNC's Dwight Jones (6-4/225/4.53) has length that equates to a large catch radius, and strength to beat a pressing corner. For a big target, Jones has underrated acceleration off the line but inconsistent hands, uninspired blocking, and an inability to evade tacklers make him a second-day pick. Former Appalachian State basketball recruit Brian Quick (6-4/216/4.63) eats up off-coverage cushion with long strides and uses his body to shield DBs, but is raw in many areas. Quick has hitches in his routes and fails to snatch the ball in the air with strong hands. Versus top competition (Virginia Tech), however, Quick has showcased vertical skills.

After college teammate Jarius Wright jumped off the page at last week's East-West Shrine, Arkansas' Joe Adams (5-11/190/4.38) will look to keep the Razorbacks' momentum. Adams has ideal size for a slot weapon and can obviously stretch the field, but needs to show he can win 50/50 balls. His return ability is an excellent bonus. TE Michael Egnew (6-5/245/4.60) was a glorified wideout at Missouri, usually lining up in a two-point stance. He is a solid receiver that can adjust to throws but rarely faced pressure off the line. Most of all, Egnew will need to show blocking effort and a willingness to get physical by sealing the edge on outside runs.

Offensive Linemen

With NFL offenses turning to pass-first game plans, Iowa State’s old-school mauler Kelechi Osemele (6-5/347/5.40) is deceptively sound in both run- and pass-blocking technique. Osemele’s best attributes are violent hands that render defensive linemen defenseless. However, he struggles at times to get in proper squared positioning because of heavy feet, which allow quicker pass rushers to beat him inside. The biggest question is where Osemele fits after playing tackle in college, but having the footwork of an interior lineman.

Alabama-Birmingham's Matt McCants (6-5/295/5.26) is just the opposite, needing to add weight to his thin frame without losing foot quickness. McCants’ posture needs work, occasionally standing straight up, but he has great flexibility and athleticism to anchor with length in pass pro. He is a potential left tackle that is already showing the physical play that will lead to strength when his frame fully develops. Quick edge rushers may beat McCants because of his long steps. Georgia C Ben Jones (6-3/316/5.26) absorbs power from interior defensive linemen well, while having necessary footwork to mirror penetrating defensive tackles. At times Jones can lunge and his athleticism and balance are exposed when asked to recover, but he is very quick off the snap to get his hands in proper placement.

A few positions are especially rich -- e.g. running back and offensive line -- but others leave room for declared juniors to emerge as top prospects. The Senior Bowl squads will be coached by two current NFL staffs (Vikings and Redskins), adding an extra dimension to their evaluations.

Just like my Shrine Week coverage, I will be constantly tweeting (@JoshNorris) and producing frequent articles. For now, here is a position-by-position preview along with my top 15 prospects entering the week. Tomorrow, I will post evaluations on players that opted out of the Senior Bowl.

All heights, weights, and forty times are projected until weigh-ins take place early Monday.

Quarterbacks

Age can be a factor when selecting a quarterback early, but Oklahoma State’s Brandon Weeden (6-4/218/4.92) may be an exception to the rule. He will be 28 once the 2012 season kicks off after exploring Minor League Baseball, but stands tall in the pocket with patience and delivers an accurate ball into tight windows. The former pitcher has NFL velocity, and Weeden's release is quick when his feet are set. If a quarterback-needy team believes it can win right away with Weeden, it should not hesitate to draft him early.

Arizona’s Nick Foles (6-5/240/4.96) has gained steam lately, with some attributing his ups and downs to a poor offensive line. Whatever the excuse, Foles is an incredibly inconsistent passer. At times he flashes the ability to make every NFL throw, but too often Foles’ lack of mobility, dropping release, and erratic decision-making lead to trouble when his feet aren't set. Wisconsin’s Russell Wilson (5-11/210/4.59) and Boise State's Kellen Moore (6-0/195/4.98) will both measure in below six feet and need to break the mold of solid college quarterbacks that lack arm talent and height to succeed at the next level.

Running Backs

A versatile, deep group of ball carriers has made its way to Mobile hoping to change the perception that their position isn't worth early-round picks due to a historically short shelf life. Boise State's Doug Martin (5-9/210/4.48) has been labeled as a power back because of his thick stature, but along with rarely going down on first contact Martin has great balance and breaks plenty of tackles. He explodes through holes with nice posture and does not lack straight-line speed. Martin has the skills of a future three-down back with soft hands and experience in pass protection. The lone issue is that Martin lacks wiggle to make defenders miss in the open field.

Closely behind is Washington’s Chris Polk (5-11/222/4.48), whose best assets are patience and vision. A tackle breaker himself, Polk follows his downfield blocks closely by weaving in and out of lanes and uses deceptive long speed to bust into the open field. Polk is another potential three-down back that has soft hands and gives effort in pass protection.

Cincinnati's Isaiah Pead (5-10/200/4.42) is a versatile playmaker with sure hands that seems to break at least one long run each game. He made his living in college with shifty moves in short spaces and excellent vision, but Pead's explosion out of breaks is not as quick as it should be for a runner that uses it as a crutch. DeMarco Murray faced similar criticism, but his skills have translated to be an effective open-field runner. Pead will need to do the same. Mississippi State’s Vick Ballard (5-10/220/4.58) and Baylor’s Terrance Ganaway (5-11/240/4.62) are between-the-tackles runners that break long runs on occasion but go down on first contact too often and have little short-area quickness to suddenly change direction.

Wide Receivers/Tight Ends

With top-rated seniors Floyd and Wright out, the rest of this year's Senior Bowl receiver group has increased opportunity to catch scouts' attention. UNC's Dwight Jones (6-4/225/4.53) has length that equates to a large catch radius, and strength to beat a pressing corner. For a big target, Jones has underrated acceleration off the line but inconsistent hands, uninspired blocking, and an inability to evade tacklers make him a second-day pick. Former Appalachian State basketball recruit Brian Quick (6-4/216/4.63) eats up off-coverage cushion with long strides and uses his body to shield DBs, but is raw in many areas. Quick has hitches in his routes and fails to snatch the ball in the air with strong hands. Versus top competition (Virginia Tech), however, Quick has showcased vertical skills.

After college teammate Jarius Wright jumped off the page at last week's East-West Shrine, Arkansas' Joe Adams (5-11/190/4.38) will look to keep the Razorbacks' momentum. Adams has ideal size for a slot weapon and can obviously stretch the field, but needs to show he can win 50/50 balls. His return ability is an excellent bonus. TE Michael Egnew (6-5/245/4.60) was a glorified wideout at Missouri, usually lining up in a two-point stance. He is a solid receiver that can adjust to throws but rarely faced pressure off the line. Most of all, Egnew will need to show blocking effort and a willingness to get physical by sealing the edge on outside runs.

Offensive Linemen

With NFL offenses turning to pass-first game plans, Iowa State’s old-school mauler Kelechi Osemele (6-5/347/5.40) is deceptively sound in both run- and pass-blocking technique. Osemele’s best attributes are violent hands that render defensive linemen defenseless. However, he struggles at times to get in proper squared positioning because of heavy feet, which allow quicker pass rushers to beat him inside. The biggest question is where Osemele fits after playing tackle in college, but having the footwork of an interior lineman.

Alabama-Birmingham's Matt McCants (6-5/295/5.26) is just the opposite, needing to add weight to his thin frame without losing foot quickness. McCants’ posture needs work, occasionally standing straight up, but he has great flexibility and athleticism to anchor with length in pass pro. He is a potential left tackle that is already showing the physical play that will lead to strength when his frame fully develops. Quick edge rushers may beat McCants because of his long steps. Georgia C Ben Jones (6-3/316/5.26) absorbs power from interior defensive linemen well, while having necessary footwork to mirror penetrating defensive tackles. At times Jones can lunge and his athleticism and balance are exposed when asked to recover, but he is very quick off the snap to get his hands in proper placement.

Defensive Linemen

Washington’s Alameda Ta’amu (6-2/337/5.22) is one of the few true nose tackles in this class, but plays much smaller. Rather than possessing a strong upper body, Ta’amu looks soft when forced to lock out and anchor versus the run. He makes too many of his tackles past the line of scrimmage. Ta'amu also prefers to penetrate a gap rather than hold his position. Marshall’s Vinny Curry (6-3/263/4.74) is thickly built and flashes a good burst off the line. Regrettably, Curry is short on quickness and ability to turn the corner, lacking fluidity and knowledge of how to disengage with his hands. Curry is a high-motor player that chases downfield but has been known to overrun his assignment.

Clemson’s Andre Branch (6-4/260/4.77) has been labeled as a pure pass rusher and will get looks as a 3-4 outside linebacker after displaying fluidity in space. His inconsistencies versus the run look to be correctable. Branch understands the importance of length and separation, but too often gives up positioning by trying to undercut the lane instead of simply disengaging. Branch’s pass-rush angles loop too much, although his excellent closing speed helps.

Linebackers

This week will feature two boom-or-bust type outside linebacker prospects. First, UNC’s Zach Brown (6-2/230/4.48) is an incredible athlete that in 2009 broke his school’s indoor track record for the 60-meter dash (6.72 seconds). Brown looks most comfortable in coverage, although he can get caught in no-man’s land. Brown is weak at the point of attack with soft hands despite great length and lacks recognition skills to flow to the football. He is the definition of a better athlete than football player. Although Brown’s ceiling is high, he would be a luxury as a first-round pick.

Utah State's Bobby Wagner (6-0/232/4.69) is not the same athlete as Brown but looks just as raw. His length, intensity, and punishing hits are intriguing, but Wagner has trouble fighting through trash and shedding blocks at the second level. Wagner has poor technique, partially due to consistently pausing when reacting. Miami’s Sean Spence (5-11/224/4.58) is an intelligent football player that will be a great downhill weak-side linebacker. Partially due to his height, Spence loses the ball carrier in the backfield too often, leading to poor reads. He is effective with a clear lane or outside the numbers but will struggle versus bigger tight ends downfield.

Defensive Backs

In a shallow safety class, South Carolina’s Antonio Allen (6-1/202/4.57) has a lot to gain this week. The box safety is comfortable in both man and zone coverage against quicker receivers or bigger tight ends. Allen’s extremely long arms help slow down receivers over the middle, hold the edge against the run, and make up extra room in coverage, where he lacks short-area quickness. Allen may be one of the first true Rover SS/LBs drafted to neutralize Joker/Move TEs. He would fill that role well.

Oklahoma’s Jamell Fleming (5-11/192/4.54) is most comfortable in press coverage, either slowing down the receiver with a jam or bailing to run with him downfield while keying on the quarterback’s eyes. Fleming struggles to stay in the receiver’s hip pocket at times but has the fluidity to recover when facing quick movements. His physical press ability also transcends versus the run, where Fleming contains the edge to prevent big gains down the sideline.

Top 15 Senior Bowl players heading into the week:

1. DE Quinton Coples (6-6/285/4.76), UNC - A team player, Coples played the ’10 season at defensive tackle and shined, creating constant penetration and anchoring well at the line of scrimmage. However, Coples failed to meet those high expectations this season after converting back to end. He consistently looked tentative or disinterested in contact, much different than the previous year when he was forced to play physical every snap. When asked to purely pass rush, Coples is tremendously successful and has the strength-athleticism combo to dominate offensive linemen. Coples may have some potential to bust after a below-average senior season, but his versatility is unparalleled. It doesn’t mater if he is a 3-4 DE, 4-3 LDE, or potential 3-Tech DT (Think Jason Jones or Chris Canty), Coples is going to be successful in the NFL and may dominate in Mobile versus quality competition.

2. RB Doug Martin (5-9/210/4.48), Boise State - Martin is an obvious favorite of mine; it is tough to find the combination of explosiveness and balance that he possesses. Martin can run inside and out while breaking tackles with a physical style, or staying up after first contact because of his low center of gravity. Add on that he’s adept as a receiver out of the backfield and delivers a pop when asked to pass protect, and it's clear Martin can carry the load in the NFL.

3. DE Melvin Ingram (6-1/276/4.82), South Carolina - Ingram exploded this year after earning a starting role. A great athlete in a thick frame, Ingram will only improve once his technique catches up to his natural gifts. Ingram will win man-leverage battles and has quickness to cleanly disengage or power to bull rush the tackle's chest. There has been talk of Ingram possibly playing 3-4 outside linebacker because of his James Harrison-like frame, but his ideal position is 4-3 end who kicks inside on obvious passing downs a la Charles Johnson of the Panthers.

4. RB Chris Polk (5-11/222/4.48), Washington - Polk waived his medical redshirt year to participate at the Senior Bowl. Polk may not have a true second gear, but his pace is deceivingly fast. He runs a bit upright at times but breaks a tremendous amount of tackles. A versatile receiver with lateral agility to bounce between running lanes, Polk is another every-down back.

5. 3-4 OLB Courtney Upshaw (6-2/265/4.76), Alabama - Consistency is Upshaw's best attribute. He gives effort on every snap, which leads to production. However, Upshaw lacks explosive qualities to his game, especially off the snap. He does not have elite athleticism to make jaw-dropping plays, but holds the edge well versus the run and is persistent in his rush, using multiple counter moves.

6. QB Brandon Weeden (6-4/218/4.92), Oklahoma State - Commonly overlooked because of age, Weeden has a great opportunity in Mobile that if aced could make him the third quarterback drafted. Weeden has top-flight arm talent and consistently stands up to pressure from the middle, but can misfire high on the move. His college offense was a bit simplistic, but QB-needy teams should not worry about a potentially shortened career if they think Weeden can start early. No front office member has seven years of job security, when Weeden will be nearing retirement age.

7. CB Alfonzo Dennard (5-10/205/4.49), Nebraska - A physical press corner, Dennard fights his opposition all the way down the field. His jam is strong and redirects routes, but Dennard can be beaten with quick steps and in off coverage when asked to turn and run vertically. He shines in man coverage while staying in the wideout's pocket and closely quickly to disrupt at the catch point.

8. OG Cordy Glenn (6-5/348/5.28), Georgia - Although he is a bit of a waist bender, Glenn rarely gets beat. I wish he had quicker feet, but Glenn shuffles to mirror nicely and absorbs contact in his upper body. It’s a bit unsettling to grade a player with poor technique this high but Glenn flashes correct posture and can dominate defensive tackles if he gets their shoulder, washing them down the line.

9. OLB Lavonte David (6-0/225/4.62), Nebraska - David’s size will be questioned, but he plays much bigger than his frame, making huge hits and fighting off larger linemen while flowing to the ball carrier. David is a great blitzer with high-end closing speed that he uses to take aggressive angles. His fluidity in coverage will keep him on the field in almost every package. David is a prototypical 4-3 WLB in the mold of Thomas Davis.

10. OT Zebrie Sanders (6-5/307/5.25), Florida State - As a senior, Sanders took over for highly-rated but injured Andrew Datko at left tackle and shined. He stays low to hit his target and has quick feet while drop stepping. Sanders' exceptional athleticism is evident when watching his lower body, but he needs a stronger punch and shorter drop steps to be even more successful. He's an interchangeable LT/RT.

11. DT Brandon Thompson (6-2/310/5.04), Clemson - Thompson was a disappointment this season. However, he has sound hand placement and great upper-body strength. Thompson steps forward when penetrating but doesn’t generate enough power from his lower body. Against the run, he occupies his gap well but fails to shed at the line of scrimmage, which limits his production.

12. OT Mike Adams (6-6/320/5.28), Ohio State - Adams is massive but flashes enough athleticism to stay at left tackle. He lacks some quickness to get to the edge on outside runs but has enough strength to grab and flow. Adams' posture is impressive for a big man, readjusting his strong hands and sitting back to anchor. He is highly susceptible to inside rushers, however.

13. OG Kevin Zeitler (6-4/318/5.26), Wisconsin - Zeitler is the latest prospect from Wisconsin’s O-Line factory. He has added a substantial amount of size since arriving in Madison but is even better with his technique when moving defensive linemen. Zeitler has a quick first step and stays low through contact, consistently getting a tight grip on his opposition to redirect them away from the hole. He is a bit raw when pass blocking, with limited athleticism to recover and anchor.

14. WR Dwight Jones (6-4/225/4.53), UNC - Jones can be a weapon at any part of the field but needs to win 50/50 balls this week. Too often he drops catchable balls but then makes spectacular grabs. I am hoping for consistency from the underrated athlete.

15. ILB James-Michael Johnson (6-1/240/4.68), Nevada - A future starting NFL middle linebacker, it's clear what a team is going to get with Johnson: He is a consistent tackler that can run downhill or fight through trash. Johnson is also fluid in coverage, sticking with crossing tight ends or down the seam. Johnson has little wasted movement in all parts of his game.